PLEASE HELP

So I found out I was pregnant and my doctor told me my child due date is April 22, 2019.

She follows up and tell me I conceived, on the 30th of July. I’ve, been researching and that makes sense. My further findings say that sex during July 25th-July 30th is most reasonably the time. I had sex on July 23, and sex on july 28th which date would be the most viable day. !!